Enum Message 

pub enum Message {
    System(String),
    User(MessageContent),
    Assistant(String),
    Tool {
        tool_call_id: String,
        content: String,
    },
}

A message in a chat conversation.

Messages can be from the system (instructions), user (input), assistant (AI response), or tool (result from a tool execution).

Variants

System(String)

System message providing instructions or context to the model.

User(MessageContent)

User message containing the user’s input (text or multimodal).

Assistant(String)

Assistant message containing the AI’s previous response.

Tool

Tool result message containing the output from a tool execution.

Important: Message Order

The xAI gRPC API matches tool results to tool calls by message order, not by ID. Tool results must be provided in the same order as the tool calls were received from the model. The tool_call_id is accepted for API compatibility with other providers (e.g., OpenAI) but is not used by xAI’s gRPC API.

Fields

tool_call_id: String

The ID of the tool call this is responding to. Note: Accepted for compatibility but not used by xAI’s gRPC API.

content: String

The content/result of the tool execution.

Trait Implementations

impl Clone for Message

fn clone(&self) -> Message

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Message

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.